Diagnostic system for a modular fieldbus board

Description

[0001] This invention relates to a diagnostic system for a modular fieldbus board, for use particularly to monitor fieldbus physical layer characteristics on a modular fieldbus bord carrying a number of fieldbuses.

[0002] In US-A-5831805 there is disclosed a local power failure detection and clock disabling circuit operating within a node coupled to a bus structure. The node includes multiple ports and physical connections for supporting multiple applications. Each physical connection serves as a bus transceiver for receiving and transmitting communications over the bus structure. The node includes a local power supply and a clock signal, which is provided to each of the physical connections within the node. A detection circuit is coupled to the local power supply for detecting whether or not a sufficient level of power is being supplied from the local power supply. The clock signal is always provided to a master physical connection within the node, which is responsible for repeating communications across the bus structure. The master physical connection draws power from the backup power supply source when the local power supply is not supplying a sufficient level of power. When the detection circuit has detected that the local power supply is not supplying a sufficient level of power, the clock signal is disabled to all of the physical connections within the node, except the master physical connection, in order to minimize power consumption of the node. The local applications coupled to the node are also disabled when a sufficient level of power is not supplied from the local power supply. When the detection circuit detects that the local power supply is again supplying power at a sufficient level, the clock signal is reenabled to all of the physical connections within the node and the local applications are also reenabled.

[0003] In US-A-5757265 there is disclosed a field bus system in which transmission ability of the system can be maintained even if communication error occurs due to noises or failure of a transmission line. The system can be easily shifted at a lower cost from a conventional system to the field bus system without degrading the high reliability thereof. The transmission line is constituted by a multiple-cable transmission line having at least three transmission cables. An external power supply supplies power to field devices through a pair of transmission cables of the multiple-cable transmission line. The field devices are connected to the transmission cables through a transmission line switching unit constituted by a plurality of rectifier elements, so that the field devices are supplied with current flowing in one predetermined direction when any of the pairs of transmission cables is selected. The external power supply monitors a failure of a currently used pair of transmission cables and, upon detection of failure of the currently used pair of transmission cables, the failed pair is replaced by a normal pair of transmission cables such that the field devices are continuously supplied with power.

[0004] In US-A1-2002/169582 there is disclosed a field device coupleable to a fieldbus process communication loop, the device comprising: a power module coupleable to the loop to power the device with energy received from the loop, a fieldbus loop communicator coupleable to the loop, and adapted to bi-directionally communicate over the loop, a controller coupled to the fieldbus loop communicator, diagnostic circuitry coupled to the controller and operably coupleable to the loop, the diagnostic circuitry adapted to measure a loop-related parameter, and wherein the controller provides diagnostic information based upon the loop-related parameter.

[0005] In WO-A-02/099663 there is disclosed an intrinsically safe field bus system comprising a field bus, a power source, a terminating resistor and at least one field bus device connected to the field bus. The power source is connected to a first end of the field bus and the terminating resistor terminates the field bus on the other end. The power source generates a periodic alternating signal, has a reactance as a terminating resistor and a unit for control and adjustment of the power source according to the input impedance (ZBus) of the field bus. The field bus input current (IBus) is kept constant when the input impedance (ZBus) in a first range of operation (I) is smaller than the wave impedance (ZW) of the field bus line, and the field bus input voltage (UBus) is adjusted to a constant maximum voltage (Umax) and the field bus input current (IBus) is adjusted according to the input impedance (ZBus) if the input impedance (ZBus) exceeds the value of the wave impedance (Zw) in a second operating range (II). In DE-A-10104908 there is disclosed an electronic device for permanent monitoring electrically measurable states or values of bus systems, such as Profibuses, field buses, etc., after the bus has been installed, with two bus conductors, a comprehensive power supply and data bus, that connects a bus master and a bus slave together. Accordingly the device samples a number of connections of the electrically measurable bus conductors using a permanent circuit connection for voltage or current measurement, testing earth connection testing the quality of the bus conductors and the signals they carry. The current testing of bus systems is based on connection of measurement meters and multimeters after installation to test the bus system and to correct any faults.

[0006] What is needed is a diagnostic system for a modular fieldbus board carrying a number of fieldbuses connected to a bulk power supply, comprises a monitoring transceiver means, such that the monitoring transceiver means can detect one or more fieldbus physical layer characteristics.

[0007] Therefore, according to the present invention a diagnostic system for a modular fieldbus board carrying a number of fieldbuses connected to a bulk power supply, comprises a monitoring transceiver means connected in use to one or more of the number of fieldbuses in which each two or more signal injection and/or signal detection points, which points are collectively adapted to inject and/or detect both common mode and differential mode signals, and which points are located between the bulk power supply and a fieldbus trunk part of the fieldbus, such that the monitoring transceiver means can detect one or more fieldbus physical layer characteristics between two of the two or more of said points and in which the monitoring transceiver means is provided with a first digital and/or analogue interface separate from the fieldbus trunk, and adapted to transmit diagnostic data detected by the monitoring transceiver means directly to an associated digital or analogue device.

[0008] Preferably the fieldbus physical layer characteristics which are monitored comprise one or more of: over/under termination, noise/ripple level, signal level, signal bias, signal jitter, signal ringing, signal distortion, signal attenuation, cross talk, unbalance, and earth leakage.

[0009] In a preferred construction the monitoring transceiver means can also detect one or more characteristics of hardware carried on the modular fieldbus board by means of one or more of said points. The hardware can be the bulk power supply connections, power supply converters, power supply conditioners and the fieldbus trunks. The characteristics to be monitored can comprise one or more of: voltage, short circuit, hardware module failure, quiescent current, and rate of charge.

[0010] The monitoring transceiver means can also be adapted to gather received data and produce one or more of: Fourier analysis, trending analysis, and data logging.

[0011] Preferably the monitoring transceiver means may be adapted to provide an alarm in the event that received data indicates one or more of predetermined failures for any of the two or more fieldbuses, and in which the first digital and/or analogue interface, is adapted to transmit said alarm directly to an associated digital or analogue device.

[0012] In one construction the first digital and/or analogue interface is adapted to receive operating commands from an associated digital or analogue device.

[0013] Alternatively, or in addition to the first interface, the monitoring transceiver means can be provided with visual means adapted to display diagnostic data detected and/or alarms created.

[0014] In addition, the monitoring transceiver means can be provided with a second digital and/or an analogue interface, such that diagnostic data detected and/or alarms created by the monitoring transceiver means can be transmitted to other associated diagnostic systems and such that data is receivable from other associated diagnostic systems.

[0015] Preferably the monitoring transceiver means can be releasably connected to or rather removable from the fieldbus board, and it can be powered in use by the bulk power supply.

[0016] In one construction one or more of the two or more common mode and/or differential mode signal injection and/or signal detection points can be disposed actually within any of the hardware carried on the board.

[0017] Preferably each of the two or more fieldbuses can comprise a connection to the bulk power supply, a power supply converter and a power supply conditioner.

[0018] It will be appreciated that the two or more common mode and/or differential mode signal injection and/or signal detection points can be dispersed at any points in the field buses. However, in a preferred construction on each of the one or more fieldbuses a first common mode signal injection and/or signal detection point can be disposed between the bulk power supply and the power supply converter, a second common mode signal injection and/or signal detection point can be disposed between the power supply converter and the power supply conditioner, a third a common mode signal injection and/or signal detection point can be disposed between the power supply conditioner and the field bus trunk, and a differential mode signal injection and/or signal detection point can be disposed between the third common mode signal injection and/or signal detection point and the fieldbus trunk.

[0019] In addition, in a preferred construction a fourth common mode signal injection and/or signal detection point can be disposed within the power supply converter, and a fifth common mode signal injection and/or signal detection point can be disposed within the power supply conditioner.

[0020] The invention can be performed in various ways, but one embodiment will now be described by way of example and with reference to Figure 1, which shows a diagrammatic display of a modular fieldbus board according to the present invention.

[0021] As shown in Figure 1, a modular fieldbus board comprises a backplane 15, on which is mounted any number of fieldbuses 8a, 8b and 8n in series and a monitoring transceiver means 17 which may also be described by those in the art as a segment autonomous diagnostic system.

[0022] The fieldbuses comprise at least fieldbuses 8a and 8b, while 8n diagrammatically signifies any number of further fieldbuses, and is therefore shown in hashed lines.

[0023] The fieldbuses 8a to 8n are connected to bulk power supply 1, and each comprise a power supply converter 3 and a power conditioner 5.

[0024] The monitoring transceiver means 17 is provided with a first digital interface, signified by arrow 16, which in use interfaces with a user operated digital control system. Further the monitoring transceiver means 17 is provided with a second digital interface, signified by hashed arrow 19, which in use can interface with similar diagnostic systems provided on associated modular fieldbus boards (not shown).

[0025] The monitoring transceiver means 17 is further provided with visual means, signified by arrows 14, which can provide information and warning signals direct to users.

[0026] The monitoring transceiver means 17 is connected to each fieldbus 8a to 8n by first common mode signal injection and detection point 2 between the bulk power supply 1 and the power supply converter 3, by second common mode signal injection and signal detection point 4 between the power supply converter 3 and the power supply conditioner 5, by third a common mode signal injection and signal detection point 6 between the power supply conditioner 5 and the field bus trunk (not shown), and by differential mode signal injection and signal detection point 7 between the third common mode signal injection and signal detection point 6 and the fieldbus trunk (not shown).

[0027] In addition, the monitoring transceiver means 17 is connected to each fieldbus by fourth common mode signal injection and signal detection point (not visible, but indicated by connection arrow 9) which is disposed within the power supply converter 3, and by fifth common mode signal injection and signal detection point (again, not visible but indicated by connection arrow 11) disposed within the power supply conditioner 5.

[0028] The monitoring transceiver means 17 can monitor for fieldbus physical layer characteristics including over/under termination, noise/ripple level, signal level, signal bias, signal jitter, signal ringing, signal distortion, signal attenuation, cross talk, unbalance, and earth leakage, between any of the above described points.

[0029] In addition, the monitoring transceiver means 17 can monitor for voltage, short circuit, hardware module failure, quiescent current, and rate of charge, between any of the above described points.

[0030] The monitoring transceiver means 17 is programmed to compile received data in use and produce Fourier analysis, trending analysis, and data logging.

[0031] Further, the monitoring transceiver means 17 is programmed to provide an alarm, either via the interfaces 16 or 19, or the visual means 14, in the event that data in use indicates one or more of pre-determined failures or the one or more fieldbuses. The indications of failures in the data are pre-programmed into the transceiver 17.

[0032] Thus, the modular fieldbus board can provide many types of information on its performance and on any potential failures to a user.

Claims

1. A diagnostic system for a modular fieldbus board carrying a number of fieldbuses (8a to 8n) connected to a bulk power supply (1), comprising a monitoring transceiver means (17) connected in use to two or more of the number of fieldbuses (8a to 8n) in which each connection to a fieldbus comprises two or more signal injection points (2, 4, 6, 7, 9 or 11) and/or signal detection points (2, 4, 6, 7, 9 or 11), which points are collectively adapted to inject and/or detect both common mode and differential mode signals, and which points (2, 4, 6, 7, 9 or 11) are located between the bulk power supply (1) and a fieldbus trunk part of the fieldbus, such that the monitoring transceiver means (17) can detect one or more fieldbus physical layer characteristics between two of the two or more of said points (2, 4, 6, 7, 9 or 11) and in which the monitoring transceiver means (17) is provided with a first digital and/or analogue interface separate from the fieldbus trunk, and adapted to transmit diagnostic data detected by the monitoring transceiver means directly to an associated digital or analogue device.

2. A diagnostic system as claimed in Claim 1, in which the fieldbus physical layer characteristics comprise one or more of: over/under termination, noise/ripple level, signal level; signal bias, signal jitter, signal ringing, signal distortion, signal attenuation, cross talk, unbalance, and earth leakage.

3. A diagnostic system as claimed in Claim 1 or 2 in which the monitoring transceiver means (17) also detects one or more characteristics of hardware (3, 5) carried on the modular fieldbus board (15) by means of one or more of said points (2, 4, 6, 7, 9 or 11).

4. A diagnostic system as claimed in Claim 3 in which the one or more characteristics of hardware comprise one or more of: voltage, short circuit, hardware module failure, quiescent current, and rate of charge.

5. A diagnostic system as claimed in Claim 1 in which the monitoring transceiver means (17) is adapted to gather received data and produce one or more of: Fourier analysis, trending analysis, and data logging.

6. A diagnostic system as claimed in any of the preceding Claims in which the monitoring transceiver means (17) is adapted to provide an alarm in the event that received data indicates that one or more of pre-determined failures has occurred on any of the two or more fieldbuses (8a to 8n), and in which the first digital and/or analogue interface is adapted to transmit said alarm directly to an associated digital or analogue device.

7. A diagnostic system as claimed in Claim 1 in which the first digital and/or analogue interface (16) (feature transferred to claim 1) is adapted to receive operating commands from an associated digital or analogue device.

8. A diagnostic system as claimed in Claim 6 in which the monitoring transceiver means (17) is provided with a second digital and/or an analogue interlace (19), such that diagnostic data detected and/or alarms generated by the monitoring transceiver means (17) are transmitted to other associated diagnostic systems and such that data is receivable from other associated diagnostic systems.

9. A diagnostic system as claimed in Claim 6 in which the monitoring transceiver means (17) is provided with visual means adapted to display diagnostic data detected and/or alarms created.

10. A diagnostic system as claimed in any of the preceding Claims in which the monitoring transceiver means (17) is releasably connected to the fieldbus board (15).

11. A diagnostic system as claimed in any of the preceding Claims in which the monitoring transceiver means (17) is connectable to the bulk power supply (1).

12. A diagnostic system as claimed in any of the preceding Claims in which one or more of the two or more signal injection points (2, 4, 6, 7,9 or 11) and/or signal detection points (2, 4, 6, 7, 9 or 11), are disposed within hardware (3, 5) on the board.

13. A diagnostic system as claimed in Claim 1 in which in each of the two or more fieldbuses (8a to 8n) comprises a connection to the bulk power supply (1), a power supply converter (3) and a power supply conditioner (5).

14. A diagnostic system as claimed in Claim 13 wherein, on each of the two or more fieldbuses (8a to 8n),
a first common mode signal injection point (2) and/or signal detection point (2) is disposed between the connection to the bulk power supply (1) and the power supply converter (3),
wherein a second common mode signal injection and/or signal detection point (4) is disposed between the power supply converter and the power supply conditioner (5),
wherein a third common mode signal injection and/or signal detection point (6) is disposed between the power supply conditioner (5) and the fieldbus trunk, and
wherein a differential mode signal injection and/or signal detection point (7) is disposed between the third common mode signal injection and/or signal detection point (6) and the fieldbus trunk.

15. A diagnostic system as claimed in Claim 14 in which a fourth common mode signal injection and/or signal detection point is disposed within the power supply converter (3), and in which a fifth common mode signal injection and/or signal detection point (11) is disposed within the power supply conditioner.

Ansprüche

1. Diagnostisches System für ein modulares Feldbus-Board, das eine Anzahl von mit einer Gesamtspannungsversorgung (1) verbundenen Feldbussen (8a bis 8n) trägt, umfassend Überwachungs-Transceivermittel (17), die in Gebrauch mit zwei oder mehr der Anzahl von Feldbussen (8a bis 8n) verbunden sind, wobei jede Verbindung mit einem Feldbus zwei oder mehr Signalinjektionspunkte (2, 4, 6, 7, 9 oder 11) und/oder Signaldetektionspunkte (2, 4, 6, 7, 9 oder 11) umfasst, welche Punkte gemeinsam angepasst sind, um sowohl Gleichtakt- als auch Differenzsignale zu injizieren und/oder zu detektieren, und welche Punkte (2, 4, 6, 7, 9 oder 11) zwischen der Gesamtspannungsversorgung (1) und einem Feldbushauptleitungsteil des Feldbuses derart angeordnet sind, dass die Überwachungs-Transceivermittel (17) eine oder mehrere Eigenschaften der physikalischen Schicht des Feldbuses zwischen zwei von den zwei oder mehreren der Punkte (2, 4, 6, 7, 9 oder 11) detektieren können, und wobei die Überwachungs-Transceivermittel (17) mit einer ersten digitalen und/oder analogen Schnittstelle bereitgestellt werden, die von der Feldbushauptleitung getrennt ist, und zum Übertragen von diagnostischen Daten, die von den Überwachungs-Transceivermitteln detektiert wurden, direkt an ein zugehöriges digitales oder analoges Gerät angepasst sind.

2. Diagnostisches System nach Anspruch 1, wobei die Eigenschaften der physikalischen Schicht des Feldbuses eines oder mehrere der Folgenden umfassen: Fehlanpassung, Rausch-/Welligkeitspegel, Signalpegel, Signalvorspannung, Signal-Jitter, Signalschwingung, Signalverzerrung, Signaldämpfung, Übersprechen, Unsymmetrie und Erdschluss (Erdkontakt).

3. Diagnostisches System nach Anspruch 1 oder 2, wobei die Überwachungs-Transceivermittel (17) auch eine oder mehrere Eigenschaften von Hardware (3, 5) detektieren, die auf dem modularen Feldbus-Board (15) durch einen oder mehrere der Punkte (2,4, 6, 7, 9 oder 11) getragen werden.

4. Diagnostisches System nach Anspruch 3, wobei eine oder mehrere Eigenschaften von Hardware eine/n/s oder mehrere der Folgenden umfassen: Spannung, Kurzschluss, Hardwaremodulversagen, Ruhestrom und Laderate.

5. Diagnostisches System nach Anspruch 1, wobei die Überwachungs-Transceivermittel (17) zum Sammeln von empfangenen Daten und Erzeugen von einer oder mehreren der Folgenden angepasst sind: Fourieranalyse, Trendanalyse und Datenerfassung.

6. Diagnostisches System nach einem der vorstehenden Ansprüche, wobei die Überwachungs-Transceivermittel (17) zum Bereitstellen eines Alarms angepasst sind in dem Fall, dass empfangene Daten angeben, dass eine oder mehrere von vorbestimmten Störungen an einem der zwei oder mehreren Feldbussen (8a bis 8n) eingetreten sind, und in welchem die erste digitale und/oder analoge Schnittstelle zur Übertragung des Alarms direkt an ein zugehöriges digitales oder analoges Gerät angepasst ist.

7. Diagnostisches System nach Anspruch 1, wobei die erste digitale und/oder analoge Schnittstelle (16) (Merkmal auf Anspruch 1 übertragen) zum Empfang von Betriebsbefehlen von einem zugehörigen digitalen oder analogen Gerät angepasst ist.

8. Diagnostisches System nach Anspruch 6, wobei die Überwachungs-Transceivermittel (17) mit einer zweiten digitalen und/oder einer analogen Schnittstelle (19) derart bereitgestellt werden, dass detektierte diagnostische Daten und/oder durch die Überwachungs-Transceivermittel (17) erzeugten Alarme auf andere zugeordnete diagnostische Systeme übertragen werden sowie derart, dass Daten von anderen zugeordneten diagnostischen Systemen empfangen werden können.

9. Diagnostisches System nach Anspruch 6, wobei die Überwachungs-Transceivermittel (17) mit visuellen Mitteln bereitgestellt werden, die zur Anzeige von detektierten diagnostischen Daten und/oder erzeugten Alarmen angepasst sind.

10. Diagnostisches System nach einem der vorstehenden Ansprüche, wobei die Überwachungs-Transceivermittel (17) mit dem Feldbus-Board (15) freigebbar verbunden sind.

11. Diagnostisches System nach einem der vorstehenden Ansprüche, in welchem die Überwachungs-Transceivermittel (17) mit der Gesamtspannungsversorgung (1) verbindbar sind.

12. Diagnostisches System nach einem der vorstehenden Ansprüche, wobei einer oder mehrere der Signalinjektionspunkte (2, 4, 6, 7, 9 oder 11) und/oder Signaldetektionspunkte (2, 4, 6, 7, 9 oder 11) innerhalb von Hardware (3, 5) auf dem Board angeordnet sind.

13. Diagnostisches System nach Anspruch 1, wobei jeder der zwei oder mehr Feldbusse (8a bis 8n) eine Verbindung mit der Gesamtspannungsversorgung (1), einen Spannungsversorgungswandler (3) und einen Spannungsversorgungsaufbereiter (5) umfasst.

14. Diagnostisches System nach Anspruch 13, wobei auf jedem der zwei oder mehr Feldbusse (8a bis 8n),
ein erster Gleichtaktsignal-Injektionspunkt (2) und/oder Signaldetektionspunkt (2) zwischen der Verbindung mit der Gesamtspannungsversorgung (1) und dem Spannungsversorgungswandler (3) angeordnet ist,
wobei ein zweiter Gleichtaktsignal-Injektionspunkt und/oder Signaldetektionspunkt (4) zwischen dem Spannungsversorgungswandler und dem Spannungsversorgungsaufbereiter (5) angeordnet ist,
wobei ein dritter Gleichtaktsignal-Injektionspunkt und/oder Signaldetektionspunkt (6) zwischen dem Spannungsversorgungsaufbereiter (5) und der Feldbushauptleitung angeordnet ist, und
wobei ein Differenzsignal-Injektionspunkt und/oder Signaldetektionspunkt (7) zwischen dem dritten Gleichtaktsignal-Injektionspunkt und/oder Signaldetektionspunkt (6) und der Feldbushauptleitung angeordnet ist.

15. Diagnostisches System nach Anspruch 14, wobei ein vierter Gleichtaktsignal-Injektionspunkt und/oder Signaldetektionspunkt in dem Spannungsversorgungswandler (3) angeordnet ist und wobei ein fünfter Gleichtaktsignal-Injektionspunkt und/oder Signaldetektionspunkt (11) in dem Spannungsversorgungsaufbereiter angeordnet ist.

Revendications

1. Système de diagnostic pour carte de bus de terrain modulaire portant un nombre de bus de terrain (8a à 8n) connectés à une alimentation électrique générale (1), comprenant un moyen émetteur-récepteur de contrôle (17) connecté en service à deux ou plusieurs du nombre de bus de terrain (8a à 8n) dans lequel chaque connexion à un bus de terrain comprend deux ou plusieurs points d'injection de signal (2, 4, 6, 7, 9 ou 11) et/ou points de détection de signal (2, 4, 6, 7, 9 ou 11), lesquels points sont adaptés collectivement pour injecter et/ou détecter à la fois des signaux de mode commun et des signaux de mode différentiel, et lesquels points (2, 4, 6, 7, 9, ou 11) sont situés entre l'alimentation électrique générale (1) et une partie de liaison de bus de terrain du bus de terrain, de telle sorte que le moyen émetteur-récepteur de contrôle (17) puisse détecter une ou plusieurs caractéristiques de couche physique de bus de terrain entre deux des deux ou plusieurs desdits points (2, 4, 6, 7, 9 ou 11) et dans lequel le moyen émetteur-récepteur de contrôle (17) est doté d'une première interface numérique et/ou analogique séparée de la liaison de bus de terrain, et adaptée pour transmettre des données de diagnostic détectées par le moyen émetteur-récepteur de contrôle directement à un dispositif numérique ou analogique associé.

2. Système de diagnostic selon la revendication 1, dans lequel les caractéristiques de couche physique de bus de terrain comprennent un ou plusieurs de : sur/sous-terminaison, niveau de bruit/ondulations, niveau de signal, polarisation de signal, gigue de signal, sonnerie de signal, distorsion de signal, atténuation de signal, diaphonie, déséquilibre et fuite à la terre.

3. Système de diagnostic selon la revendication 1 ou 2, dans lequel le moyen émetteur-récepteur de contrôle (17) détecte également une ou plusieurs caractéristiques de matériel (3, 5) exécutées sur la carte de bus de terrain modulaire (15) au moyen d'un ou de plusieurs desdits points (2, 4, 6, 7, 9 ou 11).

4. Système de diagnostic selon la revendication 3, dans lequel les une ou plusieurs caractéristiques de matériel comprennent un ou plusieurs de : tension, court-circuit, défaillance de module matériel, courant de repos, et vitesse de charge.

5. Système de diagnostic selon la revendication 1, dans lequel le moyen émetteur-récepteur de contrôle (17) est adapté pour collecter les données reçues et produire un ou plusieurs : d'une analyse de Fourier, d'une analyse de tendances et d'une consignation de données.

6. Système de diagnostic selon l'une quelconque des revendications précédentes,, dans lequel le moyen émetteur-récepteur de contrôle (17) est adapté pour produire une alarme si les données reçues indiquent qu'une ou plusieurs défaillances prédéterminées se sont produites sur n'importe lequel des deux ou plusieurs bus de terrain (8a à 8n), et dans lequel la première interface numérique et/ou analogique est adaptée pour transmettre ladite alarme directement à un dispositif numérique ou analogique associé.

7. Système de diagnostic selon la revendication 1, dans lequel la première interface numérique et/ou analogique (16) (caractéristique transférée à la revendication 1) est adaptée pour recevoir des commandes opérationnelles depuis un dispositif numérique ou analogique associé.

8. Système de diagnostic selon la revendication 6, dans lequel le moyen émetteur-récepteur de contrôle (17) est doté d'une seconde interface numérique et/ou analogique (19), de telle sorte que les données de diagnostic détectées et/ou alarmes générées par le moyen émetteur-récepteur de contrôle (17) soient transmises à d'autres systèmes de diagnostic associés et de telle sorte que les données puissent être reçues depuis d'autres systèmes de diagnostic associés.

9. Système de diagnostic selon la revendication 6, dans lequel moyen émetteur-récepteur de contrôle (17) est doté de moyens visuels adaptés pour afficher des données de diagnostic détectées et/ou des alarmes créées.

10. Système de diagnostic selon l'une quelconque des revendications précédentes, dans lequel le moyen émetteur-récepteur de contrôle (17) est connecté avec faculté de déconnexion à la carte de bus de terrain (15).

11. Système de diagnostic selon l'une quelconque des revendications précédentes, dans lequel le moyen émetteur-récepteur de contrôle (17) peut être connecté à l'alimentation électrique générale (1).

12. Système de diagnostic selon l'une quelconque des revendications précédentes, dans lequel un ou plusieurs des deux ou plusieurs points d'injection de signal (2, 4, 6, 7, 9 ou 11) et/ou points de détection de signal (2, 4, 6, 7, 9, ou 11) sont disposés dans un matériel (3, 5) sur la carte.

13. Système de diagnostic selon la revendication 1, dans lequel chacun des deux ou plusieurs bus de terrain (8a à 8n) comprend une connexion à l'alimentation électrique générale (1), un convertisseur d'alimentation électrique (3) et un conditionneur d'alimentation électrique (5).

14. Système de diagnostic selon la revendication 13, dans lequel, sur chacun des deux ou plusieurs bus de terrain (8a à 8n),
un premier point d'injection de signal (2) et/ou point de détection de signal de mode commun (2) est disposé entre la connexion à l'alimentation électrique générale (1) et le convertisseur d'alimentation électrique (3),
dans lequel un deuxième point d'injection de signal et/ou point de détection de signal de mode commun (4) est disposé entre le convertisseur d'alimentation électrique générale et le conditionneur d'alimentation électrique (5),
dans lequel un troisième point d'injection de signal et/ou point de détection de signal de mode commun (6) est disposé entre le conditionneur d'alimentation électrique (5) et la liaison de bus de terrain, et
dans lequel un point d'injection de signal et/ou point de détection de signal de mode différentiel (7) est disposé entre le troisième point d'injection de signal et/ou point de détection de signal de mode commun (6) et la liaison de bus de terrain.

15. Système de diagnostic selon la revendication 14, dans lequel un quatrième point d'injection de signal et/ou point de détection de signal de mode commun est disposé dans le convertisseur d'alimentation électrique (3), et dans lequel un cinquième point d'injection de signal et/ou point de détection de signal de mode commun (11) est disposé dans le conditionneur d'alimentation électrique.

Drawing